grammar <grammarName>;
s
@init {<LL_EXACT_AMBIG_DETECTION()>}
:   expr[0] {<ToStringTree("$expr.ctx"):writeln()>};
	expr[int _p]
		: ID 
		( 
			{5 >= $_p}? '*' expr[6]
			| {4 >= $_p}? '+' expr[5]
		)*
		;
ID  : [a-zA-Z]+ ;
WS  : [ \r\n\t]+ -> skip ;
